WASHINGTON – He may be a coaching novice, but Ben Olsen knows a thing or two about Latin American playmakers.

D.C. United’s interim boss spent most of his playing career in midfields guided by Marco Etcheverry and Christian Gómez and chased many others around the park in MLS and international play. He holds little back when discussing Columbus Crew maestro Guillermo Barros Schelotto ahead of their teams’ US Open Cup semifinal meeting at RFK Stadium on Wednesday night.

“Schelotto is one of the best players this league has ever seen, so we obviously need to deal with him,” Olsen said. “[Columbus] are a team that has been together for a while and they know what each other are about, and obviously that’s a big part of success in this league.”

The Crew will enter the match shorthanded and frazzled by a busy calendar, but the ageless Argentinean’s right foot possesses more than enough quality to sink United in their biggest game of the year. At age 37, Schelotto continues to key his workmanlike teammates with the elegant style that makes them a difficult proposition for any squad in the league.

“We know what Columbus is about,” DC goalkeeper Troy Perkins said. “They’re a physical team that relies on free kicks and balls through the middle. So if you can take out Schelotto as a playmaker, then you have a good chance. But if you let him have free rein and you give away dangerous free kicks, you’re going to put yourself in a hole.”

Olsen & Co. are clearly keen to avoid conceding set pieces in their own end – sometimes easier said than done – but the task of blunting El Mellizo’s influence in the run of play is more complicated.

“Every team has special guys that, when you look at a team, you make sure you focus on, because they’re special, they can make big plays,” Olsen said on Tuesday. “But you can’t go overboard with that stuff either, because they’ve got some other good players as well.”

Tasking a man-marker to a creator like Schelotto can disrupt your own team’s rhythm, and holding midfielder Clyde Simms may be too pivotal to the United cause to be handed such an assignment.

“Collectively, we’ve got to be able to defend properly,” Perkins said. “Do we force him out, do we force him in? Do we want him to play, then close it down? We all have to be on the same page.”

Attacking luminaries Robbie Rogers, Emmanuel Ekpo and Emilio Renteria are out, but Crew coach Robert Warzycha still has a few able bodies ready to chase down Schelotto’s cultured passes. If they are to prolong their Open Cup run, DC will need consistent defensive attentiveness against the outfit their fans have long referred to as “The Yellow Football Team.”

“I think we’re ready,” Olsen said. “Everybody knows how important this game is to us, and I think our approach will hopefully be as such. It’s been a year without a lot of ups and this is a chance for us to get into a final of an important tournament.”